Studies on the etimation of mercury contamination using basidiomycetian mushrooms and other plants as the indicator organisms.(Part II) : The process of murcurial accumulation by mushrooms

摘要

Mercury contents of selected species of mushrooms, their substrates (humus ground), leaves of woody plants, air, soil-air and exhaust gas of factory were analysed to learn the mechanism of mercury accumulation by the mushrooms. The samples were obtained from 4 stations in the vicinity of the K-Denko Factory which have still remained ten deposit sites of industrial sludge. Mercury detected in air and exhaust gas of the factory was not so higher now. But mercury levels in the soil-air of sludge deposit sites were 10 times higher than these of other stations. Neither thin gold wire nor the growing Shiitake, Lentinus edodes, left at 4 stations for about a week has trapped and accumulated the mercury from the surrounding air. In addition, mercury contents of leaves of woody plants were also negligible. Wild mushrooms and their substrates obtained from the vicinity of the factory, especially the sludge deposit sites contained higher level of mercury. There is corelation in mercury content between the mushrooms and their substrates examined in 4 species of them, Lycoperdon gemmatum, Mycena pura, Psathyrella velutina and Stropharia servginsa. However, no relationship is seen in Coprius spp. It is presumed that the mushrooms growing near the factory accumulated the mercury through the mycellium from the humus ground that has been contaminated when the acetoaldehyde plant was operated.